docs: def _region(decoder, timeout):
      """A context manager for `DmtxRegion`, created and destroyed by
      `dmtxRegionFindNext` and `dmtxRegionDestroy`.
  
      Args:
          decoder (POINTER(DmtxDecode)):
          timeout (int or None):
  
      Yields:
          DmtxRegion: The next region or None, if all regions have been found.
      """
      region = dmtxRegionFindNext(decoder, timeout)
      try:
          yield region
      finally:
          if region:
              dmtxRegionDestroy(byref(region))